400 g (13 oz) can black beans or kidney beans, rinsed and drained
125 g (4 oz) frozen or canned sweetcorn, drained if necessary
300 g (10 oz) thick beef steak
2 tablespoons lime juice
coriander leaves, to garnish
Heat 1 tablespoon of the oil in a large saucepan and cook the pepper and onion over a medium-high heat for 4–5 minutes, until lightly coloured. Reduce the heat, add the chilli, cumin and tomato purée and stir for 1 minute.
Add the stock, beans and sweetcorn, then simmer for 5–6 minutes, to allow the flavours to develop.
Meanwhile, heat the remaining tablespoon oil in a frying pan and cook the steak for 1–2 minutes each side, depending on pinkness desired. Transfer to a plate and leave to rest for 2–3 minutes. Slice the steak into strips, cutting against the grain, and pour any juices from it into the soup.
Ladle the soup into bowls, add the beef and lime juice, garnish with coriander and serve immediately, accompanied by tortilla chips and grated cheese, if desired.